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class="ear" data-v-0cd75e06></div></div> <div class="face" data-v-0cd75e06><div class="nose" data-v-0cd75e06></div> <div class="whisker-container" data-v-0cd75e06><div class="whisker" data-v-0cd75e06></div> <div class="whisker" data-v-0cd75e06></div></div> <div class="whisker-container" data-v-0cd75e06><div class="whisker" data-v-0cd75e06></div> <div class="whisker" data-v-0cd75e06></div></div></div> <div class="tail-container" data-v-0cd75e06><div class="tail" data-v-0cd75e06><div class="tail" data-v-0cd75e06><div class="tail" data-v-0cd75e06><div class="tail" data-v-0cd75e06><div class="tail" data-v-0cd75e06><div class="tail" data-v-0cd75e06><div class="tail" data-v-0cd75e06></div></div></div></div></div></div></div></div></div></div> <p class="sidebar-heading open"><span>试试 Cycle.js</span> <span class="arrow down"></span></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/front-end-playground/front-end-others/cycle-js-test/1-init-app-with-webpack.html" class="sidebar-link">1. 用 Webpack 启动应用</a></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/2-use-cyclic-router.html" class="sidebar-link">2. 使用 cyclic-router 来启动路由</a></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/3-use-typescript.html" class="sidebar-link">3. 切换到 Typescript</a></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/4-use-class-build-input.html" class="sidebar-link">4. 使用 Class 和装饰器</a></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/5-design-and-abstraction.html" class="sidebar-link">5. 关于框架设计和抽象</a></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/6-merge-streams.html" class="sidebar-link">6. 合流</a></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/7-debug-input.html" class="active sidebar-link">7. 定位 Input 组件值获取 bug</a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a href="/front-end-playground/front-end-others/cycle-js-test/7-debug-input.html#input-获取-value" class="sidebar-link">Input 获取 value</a></li><li class="sidebar-sub-header"><a href="/front-end-playground/front-end-others/cycle-js-test/7-debug-input.html#输入设置和输出更新" class="sidebar-link">输入设置和输出更新</a></li><li class="sidebar-sub-header"><a href="/front-end-playground/front-end-others/cycle-js-test/7-debug-input.html#结束语" class="sidebar-link">结束语</a></li></ul></li><li><a href="/front-end-playground/front-end-others/cycle-js-test/8-two-way-binding.html" class="sidebar-link">8. 双向绑定 Input 值</a></li></ul></section></li><li><section class="sidebar-group collapsable depth-0" style="padding-top:;"><!----> <p class="sidebar-heading"><span>D3.js 和 Tree</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0" style="padding-top:;"><!----> <p class="sidebar-heading"><span>试试 Three.js</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0" style="padding-top:;"><!----> <p class="sidebar-heading"><span>BOX2D.js 文档与教程</span> <span class="arrow right"></span></p> <!----></section></li></ul> </aside> <main class="page"> <div class="theme-default-content content__default"><p>因为对 Rxjs 的好感玩上了 Cycle.js，该系列用于记录使用该框架的一些笔记。本文将继续针对第四节中未完成的 input 值获取进行 debug，详细记录 debug 过程。</p> <h2 id="input-获取-value"><a href="#input-获取-value" aria-hidden="true" class="header-anchor">#</a> Input 获取 value</h2> <p>这里我们可以先回放第四节--<a href="https://godbasin.github.io/2017/09/08/cyclejs-notes-4-use-class-build-input/" target="_blank" rel="noopener noreferrer">《Cycle.js 学习笔记 4--使用 Class 和装饰器》<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a>。</p> <h3 id="input-class"><a href="#input-class" aria-hidden="true" class="header-anchor">#</a> Input Class</h3> <p>我们使用 Class 建立的 Input 组件是酱紫的：</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">import</span> xs <span class="token keyword">from</span> <span class="token string">&quot;xstream&quot;</span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token punctuation">{</span> run <span class="token punctuation">}</span> <span class="token keyword">from</span> <span class="token string">&quot;@cycle/run&quot;</span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token punctuation">{</span> makeDOMDriver <span class="token punctuation">}</span> <span class="token keyword">from</span> <span class="token string">&quot;@cycle/dom&quot;</span><span class="token punctuation">;</span>

<span class="token comment">// id主要是用来注册多个Input的时候抓取到对应的id</span>
<span class="token comment">// 有点简陋，但木有关系啦</span>
<span class="token keyword">let</span> id <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span>

<span class="token keyword">export</span> <span class="token keyword">class</span> <span class="token class-name">InputComponent</span> <span class="token punctuation">{</span>
  <span class="token constant">DOM</span><span class="token punctuation">;</span>
  value<span class="token punctuation">;</span>
  <span class="token function">constructor</span><span class="token punctuation">(</span><span class="token parameter">domSources<span class="token punctuation">,</span> type</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token comment">// value</span>
    <span class="token keyword">const</span> inputValue$ <span class="token operator">=</span> domSources
      <span class="token punctuation">.</span><span class="token function">select</span><span class="token punctuation">(</span><span class="token string">&quot;#input&quot;</span> <span class="token operator">+</span> id<span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">events</span><span class="token punctuation">(</span><span class="token string">&quot;keyup&quot;</span><span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token parameter">ev</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
        console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>ev<span class="token punctuation">.</span>target<span class="token punctuation">.</span>value<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token keyword">return</span> ev<span class="token punctuation">.</span>target<span class="token punctuation">.</span>value<span class="token punctuation">;</span>
      <span class="token punctuation">}</span><span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">startWith</span><span class="token punctuation">(</span><span class="token string">&quot;&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token comment">// dom</span>
    <span class="token keyword">const</span> input$ <span class="token operator">=</span> inputValue$<span class="token punctuation">.</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token parameter">val</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
      <span class="token keyword">return</span> <span class="token punctuation">(</span>
        <span class="token operator">&lt;</span>input
          type<span class="token operator">=</span><span class="token punctuation">{</span>type<span class="token punctuation">}</span>
          id<span class="token operator">=</span><span class="token punctuation">{</span><span class="token string">&quot;input&quot;</span> <span class="token operator">+</span> id<span class="token operator">++</span><span class="token punctuation">}</span>
          className<span class="token operator">=</span><span class="token string">&quot;form-control&quot;</span>
          value<span class="token operator">=</span><span class="token punctuation">{</span>val<span class="token punctuation">}</span>
        <span class="token operator">/</span><span class="token operator">&gt;</span>
      <span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span><span class="token constant">DOM</span> <span class="token operator">=</span> input$<span class="token punctuation">;</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span>value <span class="token operator">=</span> inputValue$<span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre></div><h3 id="使用-inputcomponent"><a href="#使用-inputcomponent" aria-hidden="true" class="header-anchor">#</a> 使用 InputComponent</h3> <p>我们希望通过<code>new InputComponent</code>的方式来注册这样一个双向绑定的<code>Input</code>，第四节中，我们的结果是，每次只有第一次监听和更新状态是生效的。</p> <p>这里我们通过对比的方式来进行 debug：</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">export</span> <span class="token keyword">function</span> <span class="token function">LoginComponent</span><span class="token punctuation">(</span><span class="token parameter">sources</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  <span class="token keyword">const</span> domSource <span class="token operator">=</span> sources<span class="token punctuation">.</span><span class="token constant">DOM</span><span class="token punctuation">;</span>

  <span class="token comment">// 登录点击和路由切换</span>
  <span class="token keyword">const</span> loginClick$ <span class="token operator">=</span> domSource<span class="token punctuation">.</span><span class="token function">select</span><span class="token punctuation">(</span><span class="token string">&quot;#submit&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">events</span><span class="token punctuation">(</span><span class="token string">&quot;click&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

  <span class="token comment">// 手动获取的Input值</span>
  <span class="token keyword">const</span> inputValue$ <span class="token operator">=</span> domSource
    <span class="token punctuation">.</span><span class="token function">select</span><span class="token punctuation">(</span><span class="token string">&quot;#uname&quot;</span><span class="token punctuation">)</span>
    <span class="token punctuation">.</span><span class="token function">events</span><span class="token punctuation">(</span><span class="token string">&quot;keyup&quot;</span><span class="token punctuation">)</span>
    <span class="token punctuation">.</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token parameter">ev</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
      console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>ev<span class="token punctuation">.</span>target<span class="token punctuation">.</span>value<span class="token punctuation">)</span><span class="token punctuation">;</span>
      <span class="token keyword">return</span> ev<span class="token punctuation">.</span>target<span class="token punctuation">.</span>value<span class="token punctuation">;</span>
    <span class="token punctuation">}</span><span class="token punctuation">)</span>
    <span class="token punctuation">.</span><span class="token function">startWith</span><span class="token punctuation">(</span><span class="token string">&quot;&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

  <span class="token comment">// 通过InputComponent注册的Input和值</span>
  <span class="token keyword">const</span> pwdInputSource <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">InputComponent</span><span class="token punctuation">(</span>domSource<span class="token punctuation">,</span> <span class="token string">&quot;password&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token keyword">const</span> pwdInputDOM$ <span class="token operator">=</span> pwdInputSource<span class="token punctuation">.</span><span class="token constant">DOM</span><span class="token punctuation">;</span>
  <span class="token keyword">const</span> pwdInputValue$ <span class="token operator">=</span> pwdInputSource<span class="token punctuation">.</span>value<span class="token punctuation">;</span>

  <span class="token comment">// 合流生成最终DOM流</span>
  <span class="token keyword">const</span> loginView$ <span class="token operator">=</span> xs
    <span class="token punctuation">.</span><span class="token function">combine</span><span class="token punctuation">(</span>inputValue$<span class="token punctuation">,</span> pwdInputDOM$<span class="token punctuation">,</span> pwdInputValue$<span class="token punctuation">)</span>
    <span class="token punctuation">.</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token punctuation">(</span><span class="token parameter"><span class="token punctuation">[</span>inputValue<span class="token punctuation">,</span> pwdDOM<span class="token punctuation">,</span> pwdValue<span class="token punctuation">]</span></span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
      <span class="token keyword">return</span> <span class="token punctuation">(</span>
        <span class="token operator">&lt;</span>form<span class="token operator">&gt;</span>
          <span class="token operator">&lt;</span>h1<span class="token operator">&gt;</span>System<span class="token operator">&lt;</span><span class="token operator">/</span>h1<span class="token operator">&gt;</span>
          <span class="token operator">&lt;</span>div<span class="token operator">&gt;</span>
            <span class="token operator">&lt;</span>input
              type<span class="token operator">=</span><span class="token string">&quot;text&quot;</span>
              id<span class="token operator">=</span><span class="token string">&quot;uname&quot;</span>
              className<span class="token operator">=</span><span class="token string">&quot;form-control&quot;</span>
              value<span class="token operator">=</span><span class="token punctuation">{</span>inputValue<span class="token punctuation">}</span>
            <span class="token operator">/</span><span class="token operator">&gt;</span>
          <span class="token operator">&lt;</span><span class="token operator">/</span>div<span class="token operator">&gt;</span>
          <span class="token punctuation">{</span>inputValue<span class="token punctuation">}</span>
          <span class="token operator">&lt;</span>div<span class="token operator">&gt;</span><span class="token punctuation">{</span>pwdDOM<span class="token punctuation">}</span><span class="token operator">&lt;</span><span class="token operator">/</span>div<span class="token operator">&gt;</span>
          <span class="token punctuation">{</span>pwdValue<span class="token punctuation">}</span>
          <span class="token operator">&lt;</span>div<span class="token operator">&gt;</span>
            <span class="token operator">&lt;</span>a className<span class="token operator">=</span><span class="token string">&quot;btn btn-default&quot;</span> id<span class="token operator">=</span><span class="token string">&quot;submit&quot;</span><span class="token operator">&gt;</span>
              Login
            <span class="token operator">&lt;</span><span class="token operator">/</span>a<span class="token operator">&gt;</span>
          <span class="token operator">&lt;</span><span class="token operator">/</span>div<span class="token operator">&gt;</span>
        <span class="token operator">&lt;</span><span class="token operator">/</span>form<span class="token operator">&gt;</span>
      <span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token keyword">return</span> <span class="token punctuation">{</span>
    <span class="token constant">DOM</span><span class="token punctuation">:</span> loginView$<span class="token punctuation">,</span>
    router<span class="token punctuation">:</span> loginClick$<span class="token punctuation">.</span><span class="token function">mapTo</span><span class="token punctuation">(</span><span class="token string">&quot;/app&quot;</span><span class="token punctuation">)</span>
  <span class="token punctuation">}</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>很明显，手动获取的<code>inputValue</code>能响应 input 更新状态，但通过<code>InputComponent</code>注册的 Input 和值只有第一次才能更新状态。</p> <p>开始的时候，本骚年一直以为是 Driver 驱动的问题，但是这样对比一看，原因一下子出来了[捂脸]：
因为每次更新状态后，<code>pwdDOM</code>的值更新了，虽然生成一个完全一样的 input，但是由于是个变量，因此每次都是移除重新种植。</p> <p>故原有的 input 被移除，连同在它上面绑定的监听事件一起。</p> <h3 id="实现"><a href="#实现" aria-hidden="true" class="header-anchor">#</a> 实现</h3> <p>要拿到 Input 的实时 value，本骚年想到了三种方法：</p> <ol><li>只针对<code>value</code>进行绑定，即手动获取的 Input 值，并且手动写 DOM。</li> <li>不更新<code>InputComponent</code>的基本 DOM，只更新里面的 value。</li> <li>将输入和输出拆离，也就是设置输入，以及将状态更新流出。</li></ol> <p>第一种方法，写了跟没写似的，没多少用处，故我们直接略过实现第二种吧。</p> <p>第二种方法，我们要实现除了初始化之外，每次更新值不更新对应的 DOM，其实也没有多难，我们可以通过缓存的方式来进行：</p> <ul><li>初始化的时候缓存 DOM。</li> <li>每次更新获取 DOM 并更新值。</li></ul> <p>其实这跟很多的框架是一样的，像 Angular、React、Vue 等，无非是实现虚拟 DOM、或者其他方式的 diff 过程。
具体大家可以翻阅不同代码的源码，这里就不多说了。有个 React 的虚拟 DOM 实现文章可以参考：<a href="https://github.com/livoras/blog/issues/13" target="_blank" rel="noopener noreferrer">《深度剖析：如何实现一个 Virtual DOM 算法》<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a>。</p> <p>好吧，我们来做第三种。</p> <h2 id="输入设置和输出更新"><a href="#输入设置和输出更新" aria-hidden="true" class="header-anchor">#</a> 输入设置和输出更新</h2> <h3 id="输入输出与双向绑定"><a href="#输入输出与双向绑定" aria-hidden="true" class="header-anchor">#</a> 输入输出与双向绑定</h3> <p>其实双向绑定无非是个输入设置和输出更新的语法糖，像 Angular 里面就是：</p> <div class="language-html extra-class"><pre class="language-html"><code><span class="token comment">&lt;!--双向绑定 ( [(...)] ) --&gt;</span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>my-sizer</span> <span class="token attr-name">[(size)]</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">&quot;</span>fontSizePx<span class="token punctuation">&quot;</span></span><span class="token punctuation">&gt;</span></span><span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>my-sizer</span><span class="token punctuation">&gt;</span></span>

<span class="token comment">&lt;!--双向绑定=属性绑定+事件绑定--&gt;</span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>my-sizer</span> <span class="token attr-name">[size]</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">&quot;</span>fontSizePx<span class="token punctuation">&quot;</span></span> <span class="token attr-name">(sizeChange)</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">&quot;</span>fontSizePx=$event<span class="token punctuation">&quot;</span></span><span class="token punctuation">&gt;</span></span><span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>my-sizer</span><span class="token punctuation">&gt;</span></span>
</code></pre></div><p>这里我们的 Input 则会有三种方法：</p> <ol><li>获取 DOM。</li> <li>设置 DOM 的 value。</li> <li>获取 DOM 的 value。</li></ol> <h3 id="实现输入设置和输出更新"><a href="#实现输入设置和输出更新" aria-hidden="true" class="header-anchor">#</a> 实现输入设置和输出更新</h3> <p>我们根据上面的想法，初步预设这样的思路：</p> <ul><li><code>set value</code>：该流将作为 DOM 的源，可更新 DOM 值</li> <li><code>get value</code>：该流以 DOM 为源，更获取 DOM 的更新</li> <li><code>dom</code>：以<code>set value</code>为源，且为<code>get value</code>的源</li></ul> <p>这样我们其实可以脱离调用者的<code>sources</code>了，初步实现：</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">let</span> id <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span>

@bindMethods
<span class="token keyword">export</span> <span class="token keyword">class</span> <span class="token class-name">InputComponent</span> <span class="token punctuation">{</span>
  id<span class="token punctuation">;</span>
  <span class="token constant">DOM</span><span class="token punctuation">;</span>
  inputGet<span class="token punctuation">;</span>
  inputSet<span class="token punctuation">;</span>
  <span class="token function">constructor</span><span class="token punctuation">(</span><span class="token parameter">domSource<span class="token punctuation">,</span> type</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span>id <span class="token operator">=</span> id<span class="token operator">++</span><span class="token punctuation">;</span>
    <span class="token comment">// 给设置值预留，初始化流为undefined</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span>inputSet <span class="token operator">=</span> xs<span class="token punctuation">.</span><span class="token function">of</span><span class="token punctuation">(</span><span class="token keyword">undefined</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

    <span class="token comment">// 接上设置流</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span><span class="token constant">DOM</span> <span class="token operator">=</span> xs
      <span class="token punctuation">.</span><span class="token function">merge</span><span class="token punctuation">(</span><span class="token keyword">this</span><span class="token punctuation">.</span>inputSet<span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token parameter">val</span> <span class="token operator">=&gt;</span> <span class="token punctuation">(</span>
        <span class="token operator">&lt;</span>input
          type<span class="token operator">=</span><span class="token punctuation">{</span>type<span class="token punctuation">}</span>
          id<span class="token operator">=</span><span class="token punctuation">{</span><span class="token string">&quot;input&quot;</span> <span class="token operator">+</span> <span class="token keyword">this</span><span class="token punctuation">.</span>id<span class="token punctuation">}</span>
          className<span class="token operator">=</span><span class="token string">&quot;form-control&quot;</span>
          value<span class="token operator">=</span><span class="token punctuation">{</span>val<span class="token punctuation">}</span>
        <span class="token operator">/</span><span class="token operator">&gt;</span>
      <span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

    <span class="token comment">// 获取对应的值</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span>inputGet <span class="token operator">=</span> domSource
      <span class="token punctuation">.</span><span class="token function">select</span><span class="token punctuation">(</span><span class="token string">&quot;#input&quot;</span> <span class="token operator">+</span> <span class="token keyword">this</span><span class="token punctuation">.</span>id<span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">events</span><span class="token punctuation">(</span><span class="token string">&quot;keyup&quot;</span><span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token parameter">ev</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
        console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>ev<span class="token punctuation">.</span>target<span class="token punctuation">.</span>value<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token keyword">return</span> ev<span class="token punctuation">.</span>target<span class="token punctuation">.</span>value<span class="token punctuation">;</span>
      <span class="token punctuation">}</span><span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token function">startWith</span><span class="token punctuation">(</span><span class="token string">&quot;&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
  <span class="token function">getDOM</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token keyword">this</span><span class="token punctuation">.</span><span class="token constant">DOM</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
  <span class="token function">getValue</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token keyword">this</span><span class="token punctuation">.</span>inputGet<span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
  <span class="token function">setValue</span><span class="token punctuation">(</span><span class="token parameter">val</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token comment">// 待实现</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre></div><p>这里我们将流的入口流和出口流拆开了，这样就能拿到每次 input 更新的流了。至于设置值的方法还没想好，应该可以参考参考 Driver 的设计。</p> <p>这次我们能正常获取手动设置的 input，以及通过注册设置的 input 的值啦。</p> <h2 id="结束语"><a href="#结束语" aria-hidden="true" class="header-anchor">#</a> 结束语</h2> <p>这节主要围绕上一次的无法获取到 input 更新值的问题，进行 debug 并解决。<br>
但目前还木有完全实现双向绑定，其中缺了一个就是<code>set value</code>的实现，这块我们后面可以跟 driver 驱动一起讲。<br> <a href="https://github.com/godbasin/godbasin.github.io/tree/blog-codes/cyclejs-notes/7-debug-input" target="_blank" rel="noopener noreferrer">此处查看项目代码<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a><br> <a href="http://cyclejs-notes.godbasin.com/7-debug-input/index.html" target="_blank" rel="noopener noreferrer">此处查看页面效果<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a></p></div> <!----> <footer class="page-edit"><div class="edit-link"><a href="https://github.com/godbasin/front-end-playground/edit/sourcecode/docs/front-end-others/cycle-js-test/7-debug-input.md" target="_blank" rel="noopener noreferrer">帮阿猪改善此页面！</a> <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></div> <!----> <blockquote>部分文章中使用了一些网站的截图，如果涉及侵权，请告诉我删一下谢谢~</blockquote> <div style="margin-top:30px;"><div class="el-row" style="margin-left:-10px;margin-right:-10px;"><div class="el-col el-col-24 el-col-sm-0 el-col-md-2 el-col-lg-4" style="padding-left:10px;padding-right:10px;display:block;"><div style="width:1px;height:1px;"></div></div> <div class="el-col el-col-24 el-col-sm-24 el-col-md-18 el-col-lg-16" style="padding-left:10px;padding-right:10px;"><div class="el-card box-card is-always-shadow"><div class="el-card__header"><div class="clearfix"><span>温馨提示喵</span></div></div><div class="el-card__body"> <div class="el-row" style="margin-left:-10px;margin-right:-10px;"><div class="el-col el-col-24 el-col-xs-24 el-col-sm-12" style="padding-left:10px;padding-right:10px;"><div class="el-image"><div class="image-slot"><img src="https://github-imglib-1255459943.cos.ap-chengdu.myqcloud.com/assets/img/loading.gif" style="width:100%;"></div><!----></div></div> <div class="el-col el-col-24 el-col-xs-24 el-col-sm-12" style="padding-left:10px;padding-right:10px;"><div class="copyright-text"><div>本文版权归作者所有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。</div> <div>出处：被删的前端游乐场</div> <div>作者：<a href="https://github.com/godbasin" target="_blank">被删</a></div></div></div></div></div></div></div></div></div></footer> <div class="page-nav"><p class="inner"><span class="prev">
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